There are many environments in which multiple tools and disposables are used, including for example operation rooms, aircraft hangars, garages, or the like.
An operation room is a facility in which intrusive operations are performed on patients. Typically, multiple people participate in an operation, for example a surgeon, an assistant surgeon, an anesthesiologist, a scrub nurse, and a circulating nurse. The participating personnel members use multiple tools, such as scalpels, forceps, and others, varying according to the surgery being performed.
Intensive efforts are invested in keeping track of all tools and disposables, in order to make sure no tool unintentionally remains inside the patient's body. Therefore careful counting is performed before, during and after the operation.
Counting the tools is a tedious job and requires intensive resources, including mental resources, personnel time and down-time of the operating room. Counting the tools towards the end of an operation also increases the time the patient's body is open with the associated risks.
In addition, counting is not always error-free, and there have been cases in which tools end up being left within the patient's body, causing severe damage and even death.
Another problem relates to the life cycle of tools. For example, the tools used in an operation have to be washed and/or sterilized prior to further usage. Other constraints may relate to maintenance operations required for the tools, for example, a blade may have to be sharpened after every predetermined number of operations in which it is used. In another example, tools that have been used in an operation performed on a patient with a contagious disease may require extra sterilization before further usage, or the like. Making sure that each tool is used and maintained properly also imposes expenses and requires resources, including record keeping and tracking, manual labor and the like.
A computerized system for counting, keeping track of the tools and their maintenance is desirable to enhance dealing with the tools. Such a system needs to uniquely identify each tool. In U.S. Pat. No. 8,193,938 to Halberthal et al dated Jun. 5, 2012 there is disclosed a system and method for keeping track of tools. Identifying tools is performed using a Radio Frequency (RF) identification transducer tag that is attached to the tools.
A tag reader is required to read the tags in a reliable manner. Typically specific shaped containers with stationary readers are used for placing tools before and after use of the tools. The containers are equipped with readers having antennas that are tuned to read RFID tags while taking into account the antenna impedance resulting from the design of the container. It is further desirable to have a mobile reader provided for example in the form of a wand, which can be waved past or suspended in the air over a pile of tools or a container with tools and reliably record the tools based on their tags.
Another reason for using a mobile instrument reader in an operating room is that it dramatically reduces handling time of the tools. In a highly demanding environment where every second counts (staff preparing for an operation, during the operation and in preparing the operating theatre for the next operation), every second saved is monumental to the hospital, and operating team, from the standpoint of patient safety, efficient work flow and cost saving.
However when using a mobile reader instead of a specifically designed container the antenna is more susceptible to interference caused by the environment, for example when being deployed to read a group of tags the mobile reader may move near a large metal object distorting the impedance of the reader and optionally causing the reader to lock up. Likewise when reading tags from various angles the mobile reader may be positioned near various objects such as metals, liquids, people and the like, the antenna will assume different impedance values leading to unreliable results when reading a group of tags.